<?php

class Kd_Data_Dcl_Expression_Fn_String_Sub extends Kd_Data_Dcl_Expression_Fn_String_Base{

    private $_string = '';
	private $_position = 0;
	private $_length = NULL;
	
    public function __construct($string, $pos, $len = NULL) {
        $this->_string = $this->stringOrField($string);
        $this->_position = $pos;
        $this->_length = $len;
    }
    
    public function getString(){
    	return $this->_string;
    }
    
    public function getPosition(){
    	return $this->_position;
    }
    
    public function getLength(){
    	return $this->_length;
    }

    public function getFunctionType(){
        return 'string_sub';
    }
}